Microelectrode arrays (MEAs) can be used for electrophysiological measurements of excitable cells, such as neuronal cells. Electrophysiological measurements can be obtained under various conditions. For example, pharmachological studies can be performed by applying various chemical compounds onto the neuronal cells and recording the resultant electrical activities.
In various electrophysiological measurements, higher amplitude of electrophysiological signals and improved effectiveness of stimulation can be achieved by positioning neurons on or closely in the neighborhood of a recording/stimulation site. Attempts to provide such controlled positioning of neuronal cells by employing physical containment such as micro-wells and micro-channels and/or appropriate materials for surface patterning have been mostly unsatisfactory.